The most important part of tincturing is knowing the herb weight to mentruum (solvent) volume ratio. I use ounces, since that is what the old docs used and the ratios are eaier to find. At this point, I have my own DB of these values now. You also need to know the kinds of constituents in the plants so you can decide what percent of your menstruum will be alcohol. For the most resinous plants, like Cannabis, you need 95% ethyl alcohol (everclear) at a 1:2 weight to volume ratio.

The process we will us here is called maceration. It basically means soaking. For the most pain relieving Cannabis tincture, I take half of the raw material and spread it out on a cookie sheet, then put it in the oven at its lowest setting for up to 20 minutes. Leave the oven door open about three or four inches. This converts some of the THC into CBD. Chemists have a name for what happens here, I call it magic. After your time is up, or when you get nervous about the smell, take it out and mix it with the half you did not heat. For the headiest, but less anti inflammatory brew, skip that part.

Quoting: Mycelium

I am about 99% sure CBD is not a byproduct of THC. They are both cannabinoids created in different ratios depending on strain genetics. CBN however is a byproduct of THC. By exposing THC to too much light, heat, or air it can degrade to CBN. From experience with creating tinctures in the past, they do seem to make something magical happen, but I can assure it is not CBD, more likely CBN.